4G best practice [documento eletrónico] : operator strategy to launch 4G and stimulate mobile broadband usage / Paul Lambert
Annual report and accounts 2014-2015 [documento eletrónico] / Office of Communications
Annual report 2014 [documento eletrónico] / Hellenic Telecommunications and Post Commission
Relatório e contas 2014 [documento electrónico] : true belivers / Vodafone Portugal